Flexible containers as disclosed in my U.S. Pat. No. 5,524,990 have the potential to replace plastic bags and hard sided containers commonly used for storing food and other miscellaneous goods in many applications. However, these flexible containers rely on the ability of the material at the hinged corners to stand up to constant use for their closure's ability to open and close repeatedly. This need for wearability limits the materials that may be used. Additionally, the containers need not only to stand up to constant use but also to be able to seal tightly at these corners, in other words needing strength for wear and flexibility for seal. This again limits the materials that are appropriate.